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1.
Front Nutr ; 11: 1395685, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38919391

RESUMO

Background: Despite the known associations of dietary magnesium intake and estimated glomerular filtration rate (eGFR) with cardiovascular diseases, their combined effects on stroke risk remain unclear. Therefore, this study aims to explore the associations of dietary magnesium intake and eGFR with stroke risk. Methods: The National Health and Nutrition Examination Survey (NHANES) data of 37,637 adult participants (≥18 years) from 2003 to 2018 was analyzed. Dietary magnesium intake was categorized as low (≤ 254 mg/day) and normal (> 254 mg/day) based on experimental data. Multiple logistic regression analyses and interaction tests were conducted to assess the associations of dietary magnesium intake and eGFR with stroke risk, with a focus on the interaction between different chronic kidney disease (CKD) stages based on eGFR levels and dietary magnesium intake. Additional analyses included multiplicative interaction analysis, restricted cubic spline analysis, and subgroup evaluations by age, sex, and ethnicity. Results: Dietary magnesium intake and eGFR were inversely correlated with the risk of stroke. Participants with low dietary magnesium intake had a higher stroke risk than those with normal magnesium intake (odds ratio [OR] 1.09, 95% confidence interval [CI]: 1.03-1.42). Likewise, low eGFR was associated with an elevated stroke risk compared with normal eGFR (OR 1.56, 95% CI: 1.15-2.13). Furthermore, the two factors showed a multiplicative interaction effect on stroke risk (OR 1.05, 95% CI: 1.01-1.09). We observed a significant interaction between stage G3 CKD and low dietary magnesium intake (OR 1.05, 95% CI: 1.01-1.09), suggesting a potential association with stroke risk. However, similar associations were not observed for stages G4 and G5, possibly due to the smaller number of participants with G4 and G5 CKD. The restricted cubic spline analysis revealed a non-linear relationship between dietary magnesium intake, eGFR, and stroke risk. The interaction between magnesium deficiency and low eGFR persisted in participants aged >60 years, as well as in females, non-Hispanic Black people, and people of other races. Conclusion: Dietary magnesium intake and eGFR correlate negatively with stroke prevalence. Moreover, there was an interaction between dietary magnesium intake and stroke prevalence across different CKD stages. Further large-scale prospective studies are needed to analyze the potential relationship between dietary magnesium intake, eGFR, and stroke.

2.
Medicine (Baltimore) ; 103(18): e38005, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701267

RESUMO

Bladder Urothelial Carcinoma (BLCA), a prevalent and lethal cancer, lacks understanding regarding the roles and prognostic value of cuproptosis-related lncRNAs (CRLs), a novel form of cell death induced by copper. We collected RNA-seq data, clinical information, and prognostic data for 414 BLCA samples and 19 matched controls from The Cancer Genome Atlas. Using multivariate and univariate Cox regression analyses, we identified CRLs to create a prognostic signature. Patients were then divided into low- and high-risk groups based on their risk scores. We analyzed overall survival using the Kaplan-Meier method, evaluated stromal and immune scores, and explored functional differences between these risk groups with gene set enrichment analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were also conducted to understand the links between CRLs and BLCA development. We developed a prognostic signature using 4 independent CRLs: RC3H1-IT1, SPAG5-AS1, FAM13A-AS1, and GNG12-AS1. This signature independently predicted the prognosis of BLCA patients. High-risk patients had worse outcomes, with gene set enrichment analysis revealing enrichment in tumor- and immune-related pathways in the high-risk group. Notably, high-risk patients exhibited enhanced responses to immunotherapy and conventional chemotherapy drugs like sunitinib, paclitaxel, and gemcitabine. The independent prognostic signature variables RC3H1-IT1, SPAG5-AS1, FAM13A-AS1, and GNG12-AS1 predicted the prognoses of BLCA patients and provided a basis for the study of the mechanism of CRLs in BLCA development and progression, and the guidance of clinical treatments for patients with BLCA.


Assuntos
RNA Longo não Codificante , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/mortalidade , RNA Longo não Codificante/genética , Masculino , Prognóstico , Feminino , Idoso , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética , Estimativa de Kaplan-Meier , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia
3.
Proc Natl Acad Sci U S A ; 121(17): e2320345121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38630723

RESUMO

The TWIK-related acid-sensitive K+ channel 3 (TASK3) belongs to the two-pore domain (K2P) potassium channel family, which regulates cell excitability by mediating a constitutive "leak" potassium efflux in the nervous system. Extracellular acidification inhibits TASK3 channel, but the molecular mechanism by which channel inactivation is coupled to pH decrease remains unclear. Here, we report the cryo-electron microscopy structures of human TASK3 at neutral and acidic pH. Structural comparison revealed selectivity filter (SF) rearrangements upon acidification, characteristic of C-type inactivation, but with a unique structural basis. The extracellular mouth of the SF was prominently dilated and simultaneously blocked by a hydrophobic gate. His98 protonation shifted the conformational equilibrium between the conductive and C-type inactivated SF toward the latter by engaging a cation-π interaction with Trp78, consistent with molecular dynamics simulations and electrophysiological experiments. Our work illustrated how TASK3 is gated in response to extracellular pH change and implies how physiological stimuli might directly modulate the C-type gating of K2P channels.


Assuntos
Canais de Potássio de Domínios Poros em Tandem , Prótons , Humanos , Microscopia Crioeletrônica , Simulação de Dinâmica Molecular , Canais de Potássio de Domínios Poros em Tandem/metabolismo
4.
J Microbiol Methods ; 205: 106650, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36481430

RESUMO

Nocardia seriolae is a gram-positive bacterium that causes nocardiosis, threatening fish farming. Advanced nocardiosis is challenging to control; thus, accurate detection methods of the causal agent in the early disease stage are required. In this study, we developed a TaqMan fluorescence quantitative PCR (qPCR) assay for quantitative detection of N. seriolae in fish tissues and water samples. A pair of highly specific primers and a TaqMan probe were designed based on the N. seriolae 16S23S rRNA internal transcribed spacer (ITS) region. A high correlation coefficient (R2 = 0.998) of the standard curve with a 99.5% efficiency was obtained. The qPCR detection limit of the method was as low as 19.8 copies/µL, 1000 times more sensitive than conventional PCR, and has a good performance in the detection of cultured bacteria (y = -3.750× + 48.075, R2 = 0.974). Even 1.42 CFU/mL N. seriolae collected from 500 mL of natural pond water can be detected. Furthermore, a linear model for the relationship between the log of bacteria load and Cq values in water was established (y = -3.239× + 40.978), and the R2 value was 0.979. This assay was used for accurate N. seriolae detection in fish tissues, water samples, feeds and soils. This study provides a valuable tool for the early detection and control of nocardiosis in aquaculture.


Assuntos
Doenças dos Peixes , Nocardiose , Nocardia , Animais , Nocardia/genética , Nocardiose/diagnóstico , Nocardiose/veterinária , Nocardiose/microbiologia , Peixes/microbiologia , Reação em Cadeia da Polimerase , Doenças dos Peixes/diagnóstico , Doenças dos Peixes/microbiologia
5.
Front Mol Biosci ; 9: 962435, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090054

RESUMO

Background: Fatty acid metabolism (FAM)-related genes play a key role in the development of stomach adenocarcinoma (STAD). Although immunotherapy has led to a paradigm shift in STAD treatment, the overall response rate of immunotherapy for STAD is low due to heterogeneity of the tumor immune microenvironment (TIME). How FAM-related genes affect TIME in STAD remains unclear. Methods: The univariate Cox regression analysis was performed to screen prognostic FAM-related genes using transcriptomic profiles of the Cancer Genome Atlas (TCGA)-STAD cohort. Next, the consensus clustering analysis was performed to divide the STAD cohort into two groups based on the 13 identified prognostic genes. Then, gene set enrichment analysis (GSEA) was carried out to identify enriched pathways in the two groups. Furthermore, we developed a prognostic signature model based on 7 selected prognostic genes, which was validated to be capable in predicting the overall survival (OS) of STAD patients using the univariate Cox regression, least absolute shrinkage and selection operator (LASSO) regression, and multivariate Cox regression analyses. Finally, the "Estimation of STromal and Immune cells in MAlignant Tumours using Expression data" (ESTIMATE) algorithm was used to evaluate the stromal, immune, and ESTIMATE scores, and tumor purity of each STAD sample. Results: A total of 13 FAM-related genes were identified to be significantly associated with OS in STAD patients. Two molecular subtypes, which we named Group 1 and Group 2, were identified based on these FAM-related prognostic genes using the consensus clustering analysis. We showed that Group 2 was significantly correlated with poor prognosis and displayed higher programmed cell death ligand 1 (PD-L1) expressions and distinct immune cell infiltration patterns. Furthermore, using GSEA, we showed that apoptosis and HCM signaling pathways were significantly enriched in Group 2. We constructed a prognostic signature model using 7 selected FAM-related prognostic genes, which was proven to be effective for prediction of STAD (HR = 1.717, 95% CI = 1.105-1.240, p < 0.001). After classifying the patients into the high- and low-risk groups based on our model, we found that patients in the high-risk group tend to have more advanced T stages and higher tumor grades, as well as higher immune scores. We also found that the risk scores were positively correlated with the infiltration of certain immune cells, including resting dendritic cells (DCs), and M2 macrophages. We also demonstrated that elevated expression of gamma-glutamyltransferase 5 (GGT5) is significantly associated with worse OS and disease-free survival (DFS), more advanced T stage and higher tumor grade, and increased immune cell infiltration, suggesting that STAD patients with high GGT5 expression in the tumor tissues might have a better response to immunotherapy. Conclusion: FAM-related genes play critical roles in STAD prognosis by shaping the TIME. These genes can regulate the infiltration of various immune cells and thus are potential therapeutic targets worthy of further investigation. Furthermore, GGT5 was a promising marker for predicting immunotherapeutic response in STAD patients.

6.
Math Biosci Eng ; 19(9): 9079-9097, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35942750

RESUMO

Raw Moutan Cortex (RMC) is a traditional medicinal material commonly used in China. Moutan Cortex Carbon (MCC) is a processed product of RMC by stir-frying. As raw and processed products of the same Chinese herb pieces, they have different effects. RMC has the effects of clearing heat and cooling blood, promoting blood circulation and removing blood stasis, but MCC has the contrary effect of cooling blood and hemostasis. Therefore, it is necessary to distinguish them effectively. The traditional quality evaluation method of RMC and MCC still adopts character identification, and mainly relies on the working experience and sensory judgment of employees with experience. This will lead to strong subjectivity and poor repeatability. And the final evaluation result may cause inevitable errors and the processed products with different processing degrees in actual production, which affects the clinical efficacy. In this study, the electronic nose technology was introduced to objectively digitize the odor of RMC and MCC. And the discrimination model of RMC and MCC was constructed in order to establish a rapid, objective and stable quality evaluation method of RMC and MCC. According to the correlation analysis, the experiment found the content of gallic acid, 5-hydroxymethylfurfural (5-HMF), paeoniflorin and paeonol determined by high performance liquid chromatography (HPLC) had a certain correlation with their odor characteristics. Thus, partial least squares regression (PLSR) and support vector machine regression (SVR) were compared and established the chemical composition quantitative model. Results showed that the quantitative data of RMC and MCC odor could be used to predict the contents of the chemical components. It can be used for quality control of RCM and MCC.


Assuntos
Nariz Eletrônico , Paeonia , Carbono , Medicamentos de Ervas Chinesas , Humanos , Aprendizado de Máquina , Paeonia/química
7.
Int J Biol Macromol ; 205: 49-54, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35134454

RESUMO

Genetic fusion of human serum albumin to peptides is an important strategy to enhance the plasma half-life of the peptide. An inherent challenge of such method is the reduction of specific activity of the cargo peptides upon connecting at N- or C-termini of albumin. Here, we report a finding that residue 363-364 of albumin can be inserted with a peptide while maintaining the peptide activities. We insert a peptide inhibitor into this site, and at the N-terminus of albumin, for comparison. The chimeric protein displays potent inhibition (IC50 value of 30 nM) to its target (uPAR), but not the N-terminally fused construct. We also study the chimera of HSA with a cyclic peptide inhibitor of murine urokinase-type plasminogen activator grafted at either the internal site or the N-terminus. The internally peptide-grafted protein possesses a much more potent inhibition compared to the N-terminally located fusion (IC50 value of 32 nM vs 19 µM). We further demonstrate that such internal fusion does not affect albumin expression, secondary structure, and inherent drug binding activity. Thus, this work identifies a versatile insertion point inside albumin for maintaining fusion peptide activity, and opens a new avenue to expand the applications of albumin fusion technology.


Assuntos
Peptídeos , Ativador de Plasminogênio Tipo Uroquinase , Animais , Meia-Vida , Humanos , Camundongos , Peptídeos/metabolismo , Peptídeos/farmacologia , Peptídeos Cíclicos , Albumina Sérica Humana/química , Ativador de Plasminogênio Tipo Uroquinase/genética
8.
Br J Haematol ; 196(4): 1076-1085, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34783361

RESUMO

Recombinant tissue-type plasminogen activator (rtPA) is the clot lysis drug approved for clinical use, and is characterised by a short half-life and substantial inactivation by plasminogen activator inhibitor-1 (PAI-1). We previously discovered that a tPA mutation (A419Y) at the protease domain led to enhanced fibrinolysis activity. In the present study, we studied the mechanism of such mutation in enhancing the proteolytic activity, and whether such enhancement persists in reteplase, an United States Food and Drug Administration-approved tPA truncated variant. We constructed and expressed a series of reteplase-based mutants, including rPAG (glycosylated rPA), rPAG -Y (with A419Y mutant at rPAG ), rPAG -A4 (tetra-alanine mutation at 37-loop of rPAG ), and rPAG -A4/Y (with both) and evaluated their plasminogen activation and PAI-1 resistance. Surface plasmon resonance analysis showed that the rPAG had fibrin affinity comparable to full-length tPA. Moreover, rPAG -Y had 8·5-fold higher plasminogen activation and stronger tolerance to PAI-1 compared to rPAG . We also found that the mutations containing tetra-alanine (rPAG -A4 and rPAG -A4/Y) had dramatically reduced plasminogen activation and impaired clot lysis. In a pulmonary embolism murine model, rPAG -Y displayed a more efficient thrombolytic effect than rPAG . These results identified a novel mutant reteplase variant of tPA with increased fibrinolytic activity, laying the foundation for the development of a new potent fibrinolytic agent.


Assuntos
Tempo de Lise do Coágulo de Fibrina/métodos , Fibrinólise/efeitos dos fármacos , Fibrinolíticos/uso terapêutico , Ativador de Plasminogênio Tecidual/uso terapêutico , Animais , Fibrinolíticos/farmacologia , Humanos , Camundongos , Mutação Puntual , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Ativador de Plasminogênio Tecidual/farmacologia
9.
Zhongguo Zhen Jiu ; 41(11): 1211-5, 2021 Nov 12.
Artigo em Chinês | MEDLINE | ID: mdl-34762372

RESUMO

OBJECTIVE: To compare the clinical efficacy between scalp acupuncture electrical stimulation and routine scalp acupuncture for motor aphasia in subacute stage of cerebral infarction. METHODS: A total of 54 patients with motor aphasia in subacute stage of cerebral infarction were randomly divided into an observation group (27 cases, 1 case dropped off) and a control group (27 cases, 2 cases dropped off ). Both groups were treated with routine medication and language training. In the observation group, scalp acupuncture was given at bilateral lower 2/5 of the parietal and temporal anterior oblique line and temporal frontline; after the arrival of qi, the electrical stimulation with disperse-dense wave was given at the affected side and continuous wave was given at healthy side. The control group was treated with routine scalp acupuncture at lower 2/5 of the parietal and temporal anterior oblique line and temporal frontline of the affected side, once a day, five times as a course, totaling two courses of treatment. The aphasia battery of Chinese (ABC) score and Boston diagnostic aphasia examination (BDAE) grade were observed before and after treatment. The levels of oxygenated hemoglobin (HbO2), deoxyhemoglobin (D-Hb) and total hemoglobin (T-Hb) in local cerebral cortex of the two groups were measured in real time using functional near-infrared spectroscopy (fNIRS) before and after treatment. The clinical efficacy of the two groups was compared. RESULTS: After treatment, the scores of listening comprehension, retelling, naming, spontaneous conversation and BDAE grade in the two groups were improved compared with those before treatment (P<0.01, P<0.05), and those in the observation group were better than the control group (P<0.05). Compared before treatment, the levels of HbO2 and T-Hb were increased (P<0.01), and the levels of D-Hb were decreased (P<0.01) after treatment in the two groups. The levels of HbO2 and T-Hb in the observation group were higher than those in the control group (P<0.05), and the level of D-Hb was lower than that in the control group (P<0.05). The total effective rate was 92.3% (24/26) in the observation group, which was higher than 84.0% (21/25) in the control group (P<0.05). CONCLUSION: The scalp acupuncture electrical stimulation could improve cerebral circulation, activate specific functional areas of cerebral cortex, and promote the reconstruction and recovery of brain language function. Its curative effect is better than conventional scalp acupuncture.


Assuntos
Terapia por Acupuntura , Acidente Vascular Cerebral , Pontos de Acupuntura , Afasia de Broca , Infarto Cerebral/complicações , Infarto Cerebral/terapia , Estimulação Elétrica , Humanos , Couro Cabeludo , Resultado do Tratamento
10.
Food Chem ; 358: 129891, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33940290

RESUMO

Quercetin is a well-studied natural product with multiple pharmacological properties. In this study, we demonstrated that quercetin suppressed protein digestion in the intestinal fluid by inhibiting trypsin, a key digestive enzyme. However, we also observed a previously unknown property of quercetin: promoting the intestinal absorption of proteins. In addition, the promoted protein absorption was mediated by internalization of digested oligopeptides in the intestinal epithelia rather than increasing the intestinal paracellular permeability. Notably, four other flavonoids also achieved such enhanced intestinal absorption, suggesting that this effect was associated with the aglycone flavonol backbone, but not related to their inhibitory potencies against trypsin. This study demonstrates that quercetin exhibits dual effects on protein digestion and absorption: 1) suppressing protein digestion by inhibiting trypsin in the intestinal fluid; 2) promoting the intestinal absorption of oligopeptides in the intestinal villi cells.


Assuntos
Proteínas Alimentares/farmacocinética , Absorção Intestinal/efeitos dos fármacos , Quercetina/farmacologia , Animais , Líquidos Corporais/efeitos dos fármacos , Líquidos Corporais/metabolismo , Proteínas Alimentares/metabolismo , Digestão/efeitos dos fármacos , Cães , Flavonoides/farmacologia , Absorção Intestinal/fisiologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Células Madin Darby de Rim Canino , Masculino , Permeabilidade , Proteólise , Ratos Sprague-Dawley , Tripsina/metabolismo , Inibidores da Tripsina/farmacologia
11.
Inorg Chem ; 59(6): 4129-4139, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32141289

RESUMO

The capability of noble metal nanoparticles (NPs) as efficient charge transfer mediators to stimulate Schottky-junction-triggered charge flow in multifarious photocatalysis has garnered enormous attention in the past decade. Nevertheless, fine-tuning and controllable fabrication of a directional charge transport channel in metal/semiconductor heterostructures via suitable interface engineering is poorly investigated. Here, we report the progressive fabrication of a tailor-made directional charge transfer channel in Pt nanoparticles (NPs)-inlaid WO3 (Pt-WO3) nanocomposites via an efficient electrostatic layer-by-layer (LbL) self-assembly integrated with a thermal reduction treatment, by which oppositely charged metal precursor ions and polyelectrolyte building blocks were intimately and alternately assembled on the WO3 nanorods (NRs) by substantial electrostatic interaction. LbL self-assembly buildup and in situ self-etching-induced structural variation of WO3 NRs to a microsized superstructure occur simultaneously. We found that such exquisitely crafted Pt-WO3 nanocomposites exhibit conspicuously enhanced and versatile photoactivities for nonselective mineralizing of organic dye pollution and reduction of heavy metal ions at ambient conditions under both visible and simulated sunlight irradiation, demonstrating a synergistic effect. This is attributed to the imperative contribution of Pt NPs as electron traps to accelerate the directional high-efficiency electron transport from WO3 to Pt NPs, surpassing the confinement of electron transfer kinetics of WO3 owing to low conduction level. More intriguingly, photoredox catalysis can also be triggered simultaneously in the same reaction system. The primary in situ produced active species in the photocatalytic reactions were specifically analyzed, and underlying photocatalytic mechanisms were determined. Our work would provide a universal synthesis strategy for constructing various metal-decorated semiconductor nanocomposites for widespread photocatalytic utilizations.

12.
Nat Chem Biol ; 15(12): 1241-1248, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31611704

RESUMO

The Holliday junction (HJ) is a key intermediate during homologous recombination and DNA double-strand break repair. Timely HJ resolution by resolvases is critical for maintaining genome stability. The mechanisms underlying sequence-specific substrate recognition and cleavage by resolvases remain elusive. The monokaryotic chloroplast 1 protein (MOC1) specifically cleaves four-way DNA junctions in a sequence-specific manner. Here, we report the crystal structures of MOC1 from Zea mays, alone or bound to HJ DNA. MOC1 uses a unique ß-hairpin to embrace the DNA junction. A base-recognition motif specifically interacts with the junction center, inducing base flipping and pseudobase-pair formation at the strand-exchanging points. Structures of MOC1 bound to HJ and different metal ions support a two-metal ion catalysis mechanism. Further molecular dynamics simulations and biochemical analyses reveal a communication between specific substrate recognition and metal ion-dependent catalysis. Our study thus provides a mechanism for how a resolvase turns substrate specificity into catalytic efficiency.


Assuntos
Cloroplastos/metabolismo , Resolvases de Junção Holliday/metabolismo , Proteínas de Plantas/metabolismo , Resolvases de Junção Holliday/química , Simulação de Dinâmica Molecular , Conformação Proteica , Especificidade por Substrato
13.
J Inorg Biochem ; 189: 192-198, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30317065

RESUMO

Antimicrobial photodynamic therapy (aPDT) is an effective way to combat infectious diseases and antibiotic resistance. Photosensitizer is a key factor of aPDT and has triggered extensive research interest. In this study, a new asymmetric Zn(II) phthalocyanine mono-substituted with a triazatricyclodecane moiety (compound 3) and its cationic N-methylated derivative (compound 4) were synthesized. Their photodynamic antimicrobial activities were evaluated using bioluminescent bacterial strains. Compound 3 showed phototoxicity only toward the Gram-positive bacteria, whereas the cationic derivative compound 4 exhibited strong anti-bacterial activity against both Gram-positive and Gram-negative strains. These bacterial species were eradicated (>4.0 logs or 99.99% killing) at appropriate concentrations of compound 4 with 12.7 J/cm2 of red light, demonstrating compound 4 as a potent aPDT agent.


Assuntos
Indóis/química , Fármacos Fotossensibilizantes/química , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Isoindóis , Fotoquimioterapia
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